810491985205 has 16 divisors (see below), whose sum is σ = 1112064053760. Its totient is φ = 555499838592.

The previous prime is 810491985151. The next prime is 810491985223. The reversal of 810491985205 is 502589194018.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 810491985205 - 2¹⁹ = 810491460917 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5469469 + ... + 5615698.

It is an arithmetic number, because the mean of its divisors is an integer number (69504003360).

Almost surely, 2^810491985205 is an apocalyptic number.

It is an amenable number.

810491985205 is a deficient number, since it is larger than the sum of its proper divisors (301572068555).

810491985205 is a wasteful number, since it uses less digits than its factorization.

810491985205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11087268.

The product of its (nonzero) digits is 1036800, while the sum is 52.

The spelling of 810491985205 in words is "eight hundred ten billion, four hundred ninety-one million, nine hundred eighty-five thousand, two hundred five".